Erosion and particle invasion will occur when the surface of a motor train unit head is impacted by fine particles in a high speed, both of which would roughen the vehicle body surface. This would not only increase the air friction resistance of the railway vehicles during running, but also enhance the absorption capacity of the vehicle body surface, such that living beings (such as mosquitoes, etc.) are easier to be adsorbed, and the surface materials on the railway vehicles have a reduced lifetime and are difficult to be cleaned.
The composite coating in the prior art is a coating system of a polyurethane topcoat, a polyurethane intermediate layer, a polyester putty and an epoxy resin primer, in which the superficial coat is easily to be destroyed and the coating is easily to be shed as a whole when the coating system is impacted by fine particles. Accordingly, there is a need for a novel coating system to improve the anti-erosion performance.